Packing fluids and methods

Abstract

Packing fluids that include (a) an aqueous solvent, and optionally one or more water-miscible organic liquids; and (b) one or more organic cationic and/or alkali metal tungstates, molybdates, and/or silicates dissolved in the solvent are disclosed. The fluid may be substantially free of salts and esters of formic acid. The disclosure further relates to methods of making and using the packing fluids.

What is claimed is: 
     
       1. A packing fluid comprising:
 (a) an aqueous solvent; 
 (b) ammonium tungstate dissolved in the solvent; and 
 (c) one or more solid weighting agents, 
 the ammonium tungstate is in an amount such that the density of the packing fluid is from about 15 lbs/gal to about 22 lbs/gal. 
 
     
     
       2. The packing fluid of  claim 1 , wherein the fluid is substantially free of salts and esters of formic acid. 
     
     
       3. The packing fluid according to  claim 1 , further comprising one or more water-miscible organic liquids selected from the group consisting of esters, amines, alcohols, polyols, and glycol ethers. 
     
     
       4. The packing fluid according to  claim 1  having a pH of from about 7 to about 13. 
     
     
       5. The packing fluid of  claim 1 , further comprising a polymer. 
     
     
       6. The packing fluid according to  claim 5  wherein the polymer is crosslinked. 
     
     
       7. The packing fluid according to  claim 5 , wherein the polymer is selected from the group consisting of an acrylic acid polymer, an acrylic acid ester polymer; an acrylic acid derivative polymer, an acrylic acid homopolymer, an acrylic acid ester homopolymer, a poly(methyl acrylate), a poly (butyl acrylate), a poly(2-ethylhexyl acrylate), an acrylic acid ester co-polymer, a methacrylic acid derivative polymer, a methacrylic acid homopolymer, a methacrylic acid ester homopolymer, a poly(methyl methacrylate), a polyacrylamide homopolymer, an n-vinyl pyrolidone and polyacrylamide copolymer, a poly(butyl methacrylate), a poly(2-ethylhexyl methacryate)), an n-vinyl pyrolidone, an acrylamido-methyl-propane sulfonate polymer, an acrylamido-methyl-propane sulfonate derivative polymer, an acrylamido-methyl-propane sulfonate co-polymer, and an acrylic acid/acrylamido-methyl-propane sulfonate copolymer. 
     
     
       8. The packing fluid according to  claim 5  wherein the polymer has been crosslinked in a reaction comprising one or more crosslinking agents selected from the group consisting of a combination of a phenolic components or a phenolic precursor and formaldehyde or a formaldehyde precursor, a polyalkylimine, a non-toxic organic crosslinking agent that is free from metal ions, a polyalkyleneimine, a polyethyleneimine, a polyalkylenepolyamine, a water-soluble polyfunctional aliphatic amine, an arylalkylamine, and a heteroarylalkylamine.